Resin reservoir for photocuring for use in 3d printer and 3d printer

ABSTRACT

A resin tank applicable to a photocuring 3D printer includes: a tank body for containing a liquid photosensitive resin, at least one side wall of the tank body being an optically-transmissive wall; a transverse guide element arranged on the tank body; and a load-bearing element arranged inside the tank body and movable transversely along the guide element, wherein a load-bearing surface of the load-bearing element faces the optically-transmissive wall.

This application claims the priority to Chinese patent application No.201610461679.3 titled “RESIN TANK APPLICABLE TO PHOTOCURING 3D PRINTERAND 3D PRINTER,”, filed with the Chinese State Intellectual PropertyOffice on Jun. 23, 2016, which is incorporated herein by reference inits entirety.

FIELD

The present application relates to the field of 3D printers,specifically to a photosensitive resin tank and a 3D printer using theresin tank.

BACKGROUND

In current 3D printers, a resin tank and a load-bearing platform areformed separately. The liquid photosensitive resin tank is horizontallydisposed inside the frame of the 3D printer, and the load-bearingplatform can move vertically relative to the liquid photosensitive resintank.

In the printing process, a virtual shape of an object to be printed isfirst formed by a computer, and the virtual shape is split into multiplethin layers, and each thin layer has a unique cross-sectional pattern.Then, the liquid photosensitive resin in the resin tank is irradiatedwith light, so that the liquid photosensitive resin is cured to a thinlayer with the corresponding shape on the load-bearing platformaccording to the cross-sectional pattern. As the curing of each thinlayer is completed, the load-bearing platform is raised by a certaindistance, and then a subsequent thin layer is cured on a lower surfaceof the previous thin player, and thin layers are superposed layer bylayer to form a complete printed object.

However, when the volume of the three-dimensional object to be printedincreases, the load-bearing platform will be subjected to an excessivevertical load which may deform a bracket supporting or suspending theload-bearing platform. In this case, the load-bearing platform cannotmaintain the absolute vertical movement, but will produce offset,thereby adversely affecting the forming precision of thethree-dimensional object. Moreover, since the volume of the thin layerssuperposed layer by layer increases, it will accidently fall off theload-bearing platform due to the gravity. The operator has to stopprinting, thereby obtaining an incomplete printed object.

In view of the above drawbacks, current common photocuring 3D printersmay print the three-dimensional objects smaller than 254 mm×254 mm(about 14 inches), and can only he used for 3D printing of smallobjects.

SUMMARY

In view of the existing problems in the conventional art, a resin tankapplicable to a photocuring 3D printer is provided according to thepresent application, which includes: a tank body for containing a liquidphotosensitive resin, at least one side wall of the tank body being anoptically-transmissive wall; a transverse guide element arranged on thetank body; and a load-bearing element arranged inside the tank body andmovable transversely along the guide element, wherein a load-bearingsurface of the load-bearing element faces the optically-transmissivewall.

In some embodiments of the present application, there are two of theguide elements which are respectively arranged at upper portions ofsidewalls adjacent to the optically-transmissive wall.

In some embodiments of the present application, each of the guideelements is a guide screw, and an upper portion of the load-bearingelement has a nut seat configured to cooperate with the guide screw.

The guide element can he disposed on the upper portion of the side wallof the resin tank to prevent the guide element from being failed due tothe liquid photosensitive resin, especially when the guide element isembodied as a guide screw, if the guide element is stained with lots ofliquid photosensitive resin, it may not be able to rotate. When theguide screw is adopted, the top of the load-bearing element has a nutseat configured to cooperate with the guide screw, so that theload-bearing element may be vertically hung in the interior of the resintank, and the load-bearing element is capable of making transverselinear movement with the rotation of the guide screw.

In order to form larger objects on the load-bearing element, the size ofthe optically-transmissive wall of the resin tank described in thepresent application may he up to 20˜120 inches, thereby printing theobject with an interface size of 20 inches or even 120 inches.

In some embodiments of the present application, the resin tank furtherincludes a LCD display unit, which has a same area as theoptically-transmissive wall and is covered at an outer side or an innerside of the optically-transmissive wall.

In use, the liquid photosensitive resin may he irradiated by laseraccording to a certain path to allow the liquid photosensitive resin tobe cured on the load-bearing element according to a certain shape.Furthermore, a DLP projection device can be utilized, to directlyproject the pattern onto the surface of the liquid photosensitive resin,to allow the liquid photosensitive resin to be cured into the same shapeas the projected pattern. Moreover, an LCD display unit is covered at anouter side of the optically-transmissive wall, and the cross-sectionalpattern of the object to be printed is displayed by the LCD displayunit, the pattern is composed of a light-transmitting region and alight-shielding region, and then the LCD display unit is irradiated withlight so that the liquid photosensitive resin in the resin tank is curedon the load-bearing element according to the pattern displayed by theLCD display unit.

In addition, a 3D printer using the above resin tank is further providedaccording to the present application.

In some embodiments of the present application, the 3D printer furtherincludes a light source provided outside the optically-transmissivewall.

In some embodiments of the present application, when the LCD displayunit is used, the light source of the photocuring 3D printer is arrangedoutside the optically-transmissive wall and the LCD display unit.

In some embodiments of the present application, the light sourceincludes a light array with the same area as the optically-transmissivewall, and each light of the light array is able to be switched on or offindependently.

Because the side wall of the resin tank or the LCD display unit providedin the present application has a larger area, if the size of the objectto be cured does not reach the upper limit of 120 inches, then turningon the whole light array will result in waste of energy. In thisembodiment, a rectangular LED light array with the same area as the sidewall of the resin tank can he adopted, and the LED lights in a selectedarea can be turned on to irradiate the liquid photosensitive resin inthe resin tank. This arrangement does not affect the formation ofobjects, and may save energy and reduce manufacturing cost.

In some embodiments of the present application, the photocuring 3Dprinter further includes a control unit used to control the movement ofthe load-bearing element, the display pattern of the LCD display unit,and lights in the selected area of the light array to be switched on oroff.

The light irradiates the liquid photosensitive resin in the tank bodythrough the sidewall of the resin tank provided by the presentapplication, to allow the printed object to be formed transversely onthe load-bearing element, and the formed printed object is alwaysimmersed in the liquid photosensitive resin. Since the densitydifference between the cured printed object and the liquidphotosensitive resin is very small, the buoyancy provided by the liquidphotosensitive resin can substantially offset the weight of the printedobject, so that the printed object is not apt to fall off theload-bearing element, and a shearing force applied by the printed objecton the load-bearing element can be omitted. This arrangement does notneed to increase the structural strength of the transmission unitassociated with the load-bearing element, but also can increase the sizeof an object to be printed from 14 inches to 20˜120 inches.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic view of a resin tank according to an embodiment ofthe present application.

FIG. 2 is an exploded view of a photocuring 3D printer according to anembodiment of the present application.

FIG. 3 is an assembly view of a photocuring 3D printer according to anembodiment of the present application.

FIG. 4 is a schematic view showing the structure of a light sourceaccording to an embodiment of the present application.

DETAILED DESCRIPTION

As shown in FIG. 1, a resin tank 1 applicable to a photocuring 3Dprinter is provided according to an embodiment of the presentapplication, which includes a tank body 11 for containing a liquidphotosensitive resin, a transverse guide element 12 arranged on the tankbody 11, and a load-bearing element 13 arranged inside the tank body 11and capable of moving transversely along the guide element 12. At leastone side wall of the tank body 11 is an optically-transmissive wall 111,and a load-bearing surface of the load-bearing element 13 faces theoptically-transmissive wall 111.

There may be two of the guide elements 12 which are respectivelydisposed at upper portions of the sidewalls 112 adjacent to theoptically-transmissive wall 111. The guide element 12 may be embodied asa guide screw, and an upper portion of the load-bearing element 13 canbe provided with a nut seat cooperating with the guide screw. Thus, whenthe guide screw rotates, the load-bearing element 13 can transverselymove along the guide element 12 in the tank body 11, that is, theload-bearing element 13 can move towards or away from theoptically-transmissive wall 111.

In an embodiment of the present application, the size of theoptically-transmissive wall 111 can reach 20˜120 inches, which is muchlarger than 14 inches.

In an embodiment of the present application, an LCD display unit 14 isfurther covered on an inner side of an outer side of theoptically-transmissive wall 111 of the resin tank 1. The LCD displayunit 14 has the same area as the area of the optically-transmissivewall. The LCD display unit 14 can be controlled by a control system todisplay the pattern of each cross section of an object to be printed.

As shown in FIG. 1, in use, a light source (not shown in Figures)irradiates the LCD display unit 14 to make the liquid photosensitiveresin contained in the tank body 11 be cured on the load-bearing element13. FIG. 1 shows an incomplete printed object 2 attached on theload-bearing element 13 and immersed in uncured liquid photosensitiveresin,

As shown in FIG. 2 and FIG. 3, a photocuring 3D printer is furtherprovided according to the present application, and includes the aboveresin tank 1 and a light source 3. When the above LCD display unit 14 isdisposed at the outer side of the optically-transmissive wall I 11, thelight source 3 may be attached to the LCD display unit 14. The lightsource 3 first irradiates the LCD display unit 14, and then passesthrough the optically-transmissive wall 111 to irradiate the liquidphotosensitive resin contained in the tank body 11, to make the liquidphotosensitive resin be cured into the corresponding shape on theload-bearing element 13 according to the pattern displayed by the LCDdisplay unit 14. In a case that the above LCD display unit 14 isdisposed at the inner side of the optically-transmissive wall 111, thelight source 3 may be attached on the optically-transmissive wall 111.The light source first passes through the optically-transmissive wall111, and then irradiates the LCD display unit 14, to make the liquid tophotosensitive resin contained in the tank body 11 be cured into thecorresponding shape on the load-bearing element 13 according to thepattern displayed by the LCD display unit 14.

Reference is made to FIG. 4, the light source 3 includes a LED lightarray 31 and a reflector 32 disposed around the LED light array 31.Since the optically-transmissive wall 111 of the tank body 1 and the LCDdisplay unit 14 in the present application have a large size or an ultralarge size of 20˜120 inches, the area of the LED light array 31 shouldmatch this size. That is, when the optically-transmissive wall 111reaches the maximum size of 120 inches, in general, the size of the LEDlight array 31 is no larger than 120 inches; in other words, the size ofthe LED light array is smaller than or equal to the size of theoptically-transmissive wall 111. However, in the case that thephotocuring 3D printer of the present application is used to print anobject with a small size, it is not necessary to turn on all the LEDlights of the LED light array 31, and only part of the LED lights areneeded to be turned on to ensure the sufficient light intensity.Therefore, a control unit 4 may be utilized to set the number and thearea of LED lights in the LED light array 31 to be turned on accordingto the virtual size of the object to be printed. Also, the control unit14 may be further used to control the movement of the load-bearingelement 13 and the displayed pattern of the LCD display unit 14.

In an embodiment of the present application, the light source 3 furtherincludes a heat sink 33 arranged below the LED light array 31 and a fan34 arranged below the heat sink 33 and used for blowing air toward theheat sink 33, thereby dissipating heat from the light source 3.

In an embodiment of the present application, the photocuring 3D printerfurther includes an outer frame 5. The resin tank 1, the light source 3,and the control unit 4 are all provided inside the outer frame 5. Theresin tank 1 occupies most of the space in the outer frame 1.

In an embodiment of the present application, the above photocuring 3Dprinter further includes a supplying apparatus 6 for supplying liquidphotosensitive resin. The supplying device 6 is in communication withthe tank body 11 of the resin tank 1, and a detection end of thesupplying device 6 is arranged in the tank body 11, and thus, the liquidphotosensitive resin can be automatically replenished into the tank body11 according to the storage amount of the photosensitive resin in thetank body 11, to ensure that the cured object on the load-bearingelement 13 is always immersed in the liquid photosensitive resin.

When the photocuring 3D printer provided by the present application isin operation, control unit 4 controls the LCD display unit 14 to form across-sectional pattern of the object to be printed with alight-transmitting region (transparent) and a light-shielding region(non-transparent), and then, controls the LED lights in a correspondingarea in the LED light array 31 of the light source 3 to be turned onaccording to the size of the pattern. The light passes through the LCDdisplay unit 14 and the optically-transmissive wall 111 to irradiate theliquid photosensitive resin in the tank body 11, to allow the liquidphotosensitive resin to be cured into a corresponding thin layer on theload-bearing element 13. After completing the curing of one thin layer,the control unit 4 controls the LCD display unit 14 to switch to a nextcross-sectional pattern of the object to he printed, and controls theload-bearing element 13 to move along the guide element 12 in thedirection away from the optically-transmissive wall 111 by a distanceequal to the thickness of a single thin layer. The control unit 4 againturns the light source 3 on to irradiate the liquid photosensitive resinin the tank body 11, to allow a post-cured thin layer to beaccumulatively superposed on the previous thin layer. A completedprinted object is formed by repeating the above procedure.

it can be seen that with the present application, the printed object isfinally formed transversely on the load-bearing element 13 and is alwaysimmersed in the liquid photosensitive resin in the tank body 11. Thebuoyancy provided by the liquid photosensitive resin can substantiallyoffset the weight of the printed object, so that the printed object isnot apt to fall off the load-bearing element 13, and will not apply anexcessive shearing force on the load-bearing element 13, thus avoidingthe problem in the conventional art that the printing platform producesan offset in the vertical direction because the printed object isoversized. Therefore, compared with the conventional art, the size ofthe cross section of the printed object may obviously increase to 20˜120inches.

In view of this, the present application can be used to print an objectwith a larger cross-sectional size, such as 20˜120 inches, apparently italso can print an object with a size equal to or smaller than 20 inches,like the conventional object of 14 inches.

The present application is not intended to limit the definition of thesize of the resin tank, and referring to the above description, the sizeof the optically-transmissive wall of the resin tank 1 may actuallyselect any size below 120 inches, including a size of 20˜120 inches anda size equal to or smaller than 20 inches. On the other hand, since thebuoyancy provided by the liquid photosensitive resin can substantiallyoffset the weight of the printed object, the resin tank of the presentapplication can adopt a longer dimension in the direction in which thetransverse guide element extends, thereby enabling the 3D printer of thepresent application to print higher (or longer) objects.

Various embodiments of the present application have been described indetail hereinabove. Those skilled in the art should understand thatvarious modifications, variations and changes may be made to theembodiments without departing from the scope of the present application(which is limited by the claims). The interpretation of the scope of theclaims should be interpreted as a whole and in the broadest scopeconsistent with the description, and is not limited to the examples orthe embodiments in the detailed description.

What is claimed is:
 1. A resin tank applicable to a photocuring 3Dprinter, comprising: a tank body for containing a liquid photosensitiveresin, at least one side wall of the tank body being anoptically-transmissive wall; a transverse guide element arranged on thetank body; and a load-bearing element arranged inside the tank body andmovable transversely along the guide element, wherein a load-bearingsurface of the load-bearing element faces the optically-transmissivewall.
 2. The resin tank according to claim 1, wherein there are two ofthe guide elements which are respectively arranged at upper portions ofsidewalls adjacent to the optically-transmissive wall.
 3. The resin tankaccording to claim 2, wherein each of the guide elements is a guidescrew, and an upper portion of the load-bearing element has a nut seatconfigured to cooperate with the guide screw.
 4. The resin tankaccording to claim 1, wherein a size of the optically-transmissive wallranges from 20 inches to 120 inches.
 5. A photocuring 3D printer,comprising: a resin tank according claim 1, and a light source providedoutside the optically-transmissive wall.
 6. The photocuring 3D printeraccording to claim 5, wherein the photocuring 3D printer furthercomprises a LCD display unit having a same area as theoptically-transmissive wall and covered at an outer side or an innerside of the optically-transmissive wall.
 7. The photocuring 3D printeraccording to claim 6, wherein the light source is a light array.
 8. Thephotocuring 3D printer according to claim 7, wherein a size of the lightarray is no larger than 120 inches.
 9. The photocuring 3D printeraccording to claim 7, further comprising a control unit configured tocontrol lights in a selected area of the light array to be switched onor off
 10. The photocuring 3D printer according to claim 5, wherein thephotocuring 3D printer further comprises a liquid photosensitive resinsupplying device which is in communication with the tank body of theresin tank and is configured to supplement the liquid photosensitiveresin into the tank body.
 11. A photocuring 3D printer, comprising: aresin tank according to claim 2, and a light source provided outside theoptically-transmissive wall.
 12. The photocuring 3D printer according toclaim 11, wherein the photocuring 3D printer further comprises a LCDdisplay unit having a same area as the optically-transmissive wall andcovered at an outer side or an inner side of the optically-transmissivewall.
 13. The photocuring 3D printer according to claim 12, wherein thelight source is a light array.
 14. The photocuring 3D printer accordingto claim 13, wherein a size of the light array is no larger than 120inches.
 15. The photocuring 3D printer according to claim 13, furthercomprising a control unit configured to control lights in a selectedarea of the light array to be switched on or off.
 16. The photocuring 3Dprinter according to claim 11, wherein the photocuring 3D printerfurther comprises a liquid photosensitive resin supplying device whichis in communication with the tank body of the resin tank and isconfigured to supplement the liquid photosensitive resin into the tankbody.
 17. A photocuring 3D printer, comprising: a resin tank accordingto claim 3, and a light source provided outside theoptically-transmissive wall.
 18. The photocuring 3D printer according toclaim 17, wherein the photocuring 3D printer further comprises a LCDdisplay unit having a same area as the optically-transmissive wall andcovered at an outer side or an inner side of the optically-transmissivewall.
 19. The photocuring 3D printer according to claim 18, wherein thelight source is a light array.
 20. The photocuring 3D printer accordingto claim 19, wherein a size of the light array is no larger than 120inches.